Characterization of plant growth promoting bacteria isolated from red fruits. Studies on growth promotion and fruit quality in strawberry plants

Microorganisms associated to the rizosphere of plants cultivated plants for human consumption are scarcely analyzed. However,nowadays, organic farming  where the use of microbial inoculants is essential, has arisenas emergent alternative with a great commercial interest.In this study, the characterization of the bacterial microbiotic presents in the rhizosphere of strawberry and blueberry plants has been carried out. In particular, three relevant characteristics have been determined order  to classify he isolated strains as plant growth promoting bacteria (PGPB). These characteristics are: 1) the ability to produce auxins, 2) siderophores and 3)  the solubilization of phosphates presents in the medium.On the other hand, the behavior of bacterial strains previously identified as PGPB has been studied in strawberry plants  both in greenhouse and field trials. The plants located in the greenhouse, were inoculated with the endophytic strawberries isolated strains: LTE1, LTE2, LTE3, LTE4, LTE6, EF12a, EF35 and EF113, as well as with three blueberries insolated bacteria which possess a high leves of auxin production, named AC8, ACH2 and ACH7. The strawberries plants located in the field, were inoculated with the strains Hv16, Hvs8 and Rec3.At the greenhouse trials, production parameters (precocity in flowering, number and weight of fruits) as well as biometrical parameters at the end of the trial, the fresh and dry weigth of root and shoots will be analyzed. At the field trial, the following production parameters will be evaluated: number and weight of extra-early fruit (February), number and weight of early fruit (March) and number and weight of total fruit. Quality fruit parameters as color, shape, sugar content (ºBrix), acidity, pH, vitamin C and anthocyanin content will be determined twice, once in February and again at the end of the experiment. By the time, the micro and macro-nutrient will also be analyzaed

Biocontrol characterization of a bacterial collection by means of enzymatic activities and confrontation assays

Currently, there is an increasing agriculture demand, not only for human consumption, but also for feeding the cattle. This provokes an overuse of fertilizers and fungicides to maintain the standards of market and production which in turns causes serious environmental problems. Stimulated by these facts, we think that a possible solution could be the use of bacteria with PGPR activities (plant growth-promoting rhizobacteria) as well as biocontrol activities against pathogenic fungi, in order to reduce or to eliminate, in the future, the use of these harmful products.Bacteria used in this work belong to the bacterial collection of the IFAPA the Torres-Tomejil Center, and have been previously characterized by their PGP activities and for their aptitude to inhibit the in vitro growth of the phytopathogenic fungus Macrophomina phaseolina. In this study, the bacterial isolated were screened for their biocontrol enzymatic activities (catalase, oxidase, protease, amylase, chitinase and β-glucanase), as well as for hydrocyanic acid production. After that, an in vitro confrontation assay was carried out against F. oxysporum and F. proliferatum, with the bacterial strains that gave good results in biocontrol activities.From a total of 40 strains possessing enzymatic activities, the following strains have shown the higher values: strain Hr4b (nd) exhibited high cellulose, protease and amylase activities; strain B1-2a (Bacillus erophilus) possessed protease and amylase activities; C11 (non determined -nd-) and AdB1 (nd) enhanced in cellulase and protease activities; strain Hvs2 (Bacillus licheniformis) highlighted for its cellulose activity and CT197 (nd) for its chitinase one. In addition, all of them exhibited other enzymatic activities in a lesser extent. Regarding the in vitro confrontation experiment against F. oxysporum and F. proliferatum, the strains CT3 (Pseudomonas fluorecens), CT19 (Pseudomonas fluorecens), CT131 (Pseudomonas fluorecens), Hvs2, Hvs 6 (Streptomices fradiae) and Hvs 8 (Brevibacterium frigoritolerans), were found to be highly inhibitory of both fungal strains growth.As conclusion, strains CT3, CT19, CT131, Hvs2, Hvs6 and Hvs8 could be candidates to be used as biocontrol agents against phytopathogen fungi. Futures studies will be focused on investigating a commercial product able to be used under field conditions

Elastic scattering measurements for the 10C + 208Pb system at Elab = 66 MeV

Background: The influence of halo structure of 6 He, 8 B, 11Be, and 11Li nuclei in several mechanisms such as direct reactions and fusion is already established, although not completely understood. The influence of the 10C Brunnian structure is less known. Purpose: To investigate the influence of the cluster configuration of 10C on the elastic scattering at an energy close to the Coulomb barrier. Methods: We present experimental data for the elastic scattering of the 10C + 208Pb system at Elab = 66 MeV. The data are compared to the three- and the four-body continuum-discretized coupled-channels calculations assuming 9 B +p, 6 Be +α, and 8 Be +p + p configurations. Results: The experimental angular distribution of the cross sections shows the suppression of the Fresnel peak that is reasonably well reproduced by the continuum-discretized coupled-channels calculations. However, the calculations underestimate the cross sections at backward angles. Couplings to continuum states represent a small effect. Conclusions: The cluster configurations of 10C assumed in the present work are able to describe some of the features of the data. To explain the data at backward angles, experimental data for the breakup and an extension of theoretical formalism towards a four-body cluster seem to be in need to reproduce the measured angular distribution.Ministerio de España de Economía y Competitividad, el Foro Regional Europeo Fondo de Desarrollo (FEDER) FIS2017- 88410-PPrograma Horizonte 2020 de la Unión Europea Subvención No. 654002Fondos SID 2019 (Università degli Studi di Padova, Italia) CASA_SID19_01

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Quarry restoration treatments from recycled waste modify the physicochemical soil properties, composition and activity of bacterial communities and priming effect in semi-arid areas

The selection of a suitable organic amendment for recovery of semi-arid soils degraded by mining is key to the success of an ecological restoration. The aim of this research is to study the short-term responses of physicochemical, biochemical and biological properties, as well as the changes of a soil bacterial community at the genus level after application of five types of organic amendments in a limestone quarry in Almería (SE, Spain). The relationship among bacterial taxa with biochemical and physicochemical properties and priming effect from restored soils was also analysed. Six months after the application of organic amendments, the values of different soil status, such as total organic carbon, total nitrogen, assimilable phosphorus and labile organic matter forms (carbohydrates and polyphenols), basal respiration (BR) and enzymatic activities increased significantly with respect to unrestored soils. Similarly, a positive priming effect of soil organic matter mineralisation was produced by all organic amendments, being significantly higher (p < 0.05) in sewage sludge-treated soils. Bacterial diversity was higher in restored than in control soils. The restoration caused changes in soil bacterial communities' composition at the phylum and genus levels. It was observed that soil bacterial communities were significantly related to several physical, chemical and biochemical soil properties, establishing two different co-occurrence patterns between restored and unrestored soils. A first bacterial co-occurrence pattern showed significant positive correlations to pH and C/N ratio and negativity with the rest of the soil properties. The second bacterial pattern was positively correlated with carbohydrates, μg of C, priming effect, BR, β-glucosidase and phosphatase and negatively with pH and C/N ratio. It was concluded that soil bacterial communities are clearly influenced by the types of organic amendments applied. Bacterial taxa such as Taibaiella or Pseudomonas could perform key functions in the carbon cycle in restored soils.This work was supported by the Spanish FEDER-Ministry of Science, Innovation and Universities Research Project BIORESOC (CGL2017-88734-R) and AGL2017-85755-R MINECO/AEI/FEDER, UE, and FEDER-Junta de Andalucía Research Projects RESTAGRO (UAL18-RNM-A021-B) and Restoration of Abandoned Agricultural Soils in Semiarid Zones to Improve Productivity and Soil Quality and Enhance Carbon Sequestration (P18-RT-4112). Natalia Rodríguez-Berbel acknowledges a Ph.D. research grant from Spanish Government (PRE2018-084964). Isabel Miralles is grateful for funding received from the Ramón y Cajal Research Grant (RYC-2016-21191) from Spanish Ministry of Economy, Industry and Competitiveness (MINECO) and Raúl Ortega thanks his postdoctoral contract HIPATIA at University of Almería Research Plan. The authors wish to emphasize that this work was made possible by the kindness of CEMEX ESPAÑA OPERACIONES, S.L.U. (“CEMEX”) owners of the land located in the cement factory in Gádor (Almería) on which the study was carried out and BIOMASAS DEL GUADALQUIVIR, S.A. and Servicios Ambientales las Chozas, S.L. companies, for giving their composting products to this researc

Composición molecular de la materia orgánica de suelos restaurados a corto plazo en una cantera caliza en clima semiárido (Póster)

4 páginas.- 1 figuras.- 1 tablas.- 9 referencias.- Póster P4-26 presentado en el Congreso El suelo: clave para una gestión ambiental sostenible en un escenario de cambio global. IX Simposio sobre Control de la Degradación y Recuperación de Suelos CONDEGRES 2021, celebrado entre los días 24 y 25 de mayo de 2021A los proyectos BIORESOC (CGL2017-88734-R), RESTAGRO (UAL18-RNM-A021-B), INTERCARBON (CGL2016-78937-R), Proyecto PY18-4112 y a la beca predoctoral (PRE2018-084964), Ramón y Cajal (RYC-2016-21191) y contrato UAL-HIPATIA (Universidad de Almería).N